Height loss is commonly associated with spinal fractures, such as, for example, vertebral compression fractures. Spinal fractures affect a large segment of osteoporotic patients. It is estimated that approximately 700,000 spinal fractures occur annually from osteoporosis, for example. Procedures have been developed to treat spinal fractures. One such procedure is kyphoplasty. Kyphoplasty is a minimally invasive procedure that is used to treat spinal fractures, such as, for example, vertebral compression fractures by inserting an inflatable bone tamp inside a fractured vertebral body. The balloon or balloons of the inflatable bone tamp are inflated within the fractured vertebral body such that the cancellous bone of the vertebral body is pushed towards cortical walls of the vertebral body to form a cavity within the vertebral body. The cavity is then at least partially filled with a material, such as, for example, bone cement.
However, conventional inflatable bone tamps lack a means to control the longitudinal expansion of the balloon or balloons. Because longitudinal expansion of the balloon or balloons determine, at least in part, the size of a cavity created by the balloon or balloons, it is thus difficult to control the size of the cavity. That is, the size of the cavity created by the balloon or balloons may be smaller or larger than desired. In instances where the cavity is too small, a second cavity that overlaps the initial cavity may be required to increase the size of the initial cavity. In instances where the cavity is too large, the cavity is filled with more bone cement than is actually needed. Neither situation is desirable, as would be apparent to one of ordinary skill in the art.
Furthermore, conventional inflatable bone tamps often do not allow the profile of the balloon to be reduced sufficiently to prevent or reduce trauma or injury to the patient as the inflatable bone tamp is removed from the patient. That is, the profile of the balloon, even when the balloon is deflated, is too large to prevent trauma or injury to the patient. This disclosure describes improvements over these prior art technologies.